Definition of Service

[inspector23]

Please bear with me. I am seeking knowledge and interpretations.

Based upon 2008 NEC

I need help clarifying in my mind what is considered service wiring. The definition (Article 100) for service states "The conductors and equipment for delivering electric energy from the serving utility to the wiring system of the premises served."

Section 230.2 states that a building or other structurecan only have one service unless otherwise permitted.

Section 230.2(A) lists some of those conditions that are "otherwise permitted" - fire pumps, emergency, legally required, and/or optional standby systems, parallel power productions systems, etc.

Section 705.2 specifically lists photovoltaic and wind systems asexamples of a hybrid system that is covered under Article 705 (Interconnected Electric Power Production Sources). In my mind this makes each of them (solar, wind) a parallel power production system.



This questionwas on my most recent exam:

Which of the following statements aboutservice wiring is true?

a. The wiring from an optional standby generator is considered service wiring.
b. The wiring from a solar photovoltaic system is considered service wiring.
c. The wiring from a wind generator is considered service wiring.
d. The wiring from a serving utility is considered service wiring.

The correct answer on the test, with its explanation?
Answer: d. Service wiring is delivered to the premise by the serving utility.

I challenged the answer, my position being: Given my explanations above, all of theanswers are considered an additional service per 230.2(A) and therefore all were considered service wiring.

The response I was given was “According to thedefinition of service, only a utility can supply a service.”

There is no Article 100 definition for “utility”, so I am mystified.

What am I missing here?

Thanks in advance for your help. I am heading into the field and will not be able to check on the responses for 7-8 hours.

Gratefully,

 

[charlie b]

Interesting question. I hadn't thought in these terms before, so I don't have an opinion yet. But let's try thinking of it this way, and see where it leads us. What if the intent of 230.2(A) was not to say that emergency or optional standby generators are to be considered "services," and that it is acceptable to have these additional services to serve emergency and optional standby loads? What if the intent were instead to say that it is acceptable for the utility to provide a second service for the purposes of supplying emergency loads, and for the utility to provide a third service for the purposes of supplying optional standby loads? That would make "D" the correct answer to your test question.

 

[guschash]

I agree with Charlie. 230.2(A) Special conditions, states "Additional services. I interpret that to mean the untility can drop a other service to fire pumps, emergency systems etc.

gus

 

[inspector23]

Thanks, but...

Thanks, but...

Thank you for the responses.

Here is the situation. Costco and Kohl's department store both have contracts with big solar companies. According to the installer of the Costco system, Costco pays nothing for the installation but agrees to purchase ALL their power from the solar company at an agreed upon, fixed price.


Now I am just throwing out numbers for an example.


Costco uses 1000 kw per month in electricity. The energy from the solar panels produces 800 KW per month. Edison, the local utility, bills for the remaining 200 kW of usage per month.

ACCORDING TO THE ELECTRICAL CONTRACTOR INSTALLING THE SOLAR, Costco just pays the solar company for the toal 1000 KW used at the previously-agreed upon price. The solar company pays the utility bill from Edison.

Now in my mind that makes the solar company the "utility".

Even if this information is not correct and it just works like residential, where the solar simply offsets the total demand of the useage, I stlll see this as two "utilities" supplying power to the structure. Hence, two services supplying the structure.

But I have been called "hard-headed" before!

For whatever reason, this bugs me to no end and now has me on a quest.......

 

[Strife]

Please bear with me. I am seeking knowledge and interpretations.

Based upon 2008 NEC

I need help clarifying in my mind what is considered service wiring.

With all the latest, and latest and latest, I think the idea of a service is getting a little convoluted when it comes to NEC.
Personally I believe the original intent for service was :"utility supplied". And with more and more utilities supplying (be it solar, wind)......
However considering the fact that POCO has their own rules, above, beyond, and below NEC I consider service that point where POCO meets NEC.
As far as I'm aware all the solar has to comply with NEC, POCO doesn't. And I'm sure, pretty soon, there'll be solar like you describe where they don't have to comply with NEC.
Have to look into it, but I guess that would fall under separately derived systems. Which soon would have to be revised in NEC, just like service would soon need a clarification.

 

[iwire]

T
Now in my mind that makes the solar company the "utility". .

I can see the logic behind your thoughts but they are incorrect.

The solar company is not a utility. (Added note, a true 'utility' will be controlled by your areas 'utility commission' or utility board etc.)

Keep in mind the real reason for this distinction is that the NEC does not apply to utility company wiring, that wiring is covered under the NESC (National Electrical Safety Code)

If you try to say the solar company is the utility that would put the system beyond the reach of the NEC.

For what it is worth the situation you describe is very common and with utility company deregulation and so much distributed power production the rules may need to be looked at.

All that said I strongly urge you to stop rocking the boat and not try to reinvent the wheel.

 

[inspector23]

Thanks -

Thanks -

Thanks, I do appreciate the different viewpoints. Not sure exactly why this bugs me so much. I know this will date me, but the last time I was this bugged out was when that song “You light up my life" came out about 20 years ago. I COULD NOT stand that song but I also could not get it out of my head.

Then my bride suggested I have a prefrontal lobotomy, I then became an electrical inspector and it's been all good since.....

Thanks -

 

[charlie b]

Then my bride suggested I have a prefrontal lobotomy. . . .

I thought that was a prerequisite for getting married, or at least that is what I was told 30 years ago. :happyyes:

Things have changed, however. The "new" frontal lobotomy is called a bottlin frontome. :lol:

 

[Strathead]

The codes intent

The codes intent

My belief is that the intent of this part of the code is to prevent stepping on toes between the Utlitity Company codes and the NEC. The NEC does not cover Utlity Company work, and so the NEC needed to clearly indicate the separation point. Remember that a private industrial park could theoretically pay for a single 500,000 Volt system and every bit of wiring fromthere on is not part of the Utility. I think the NEC would have a problem with providing guidance on all of the subsequent wiring, so the facility would need to adopt a utility code for these portions.

All of that said, I am a little surprised that no one has mentioned that all of the optional systems listed by the OP are designated as separately derived systems by the code and that is what they are. A service is ONLY a utility provided electrical source. Just the way it is.

 

[Smart $]

The definition (Article 100) for service states "The conductors and equipment for delivering electric energy from the serving utility to the wiring system of the premises served."

Please note both the preceding and the following highlighted words...

a. The wiring from an optional standby generator is considered service wiring.
b. The wiring from a solar photovoltaic system is considered service wiring.
c. The wiring from a wind generator is considered service wiring.
d. The wiring from a serving utility is considered service wiring.

An additional service may be required for grid-tied parallel power production systems... but the wiring "from" those systems is not part of the service. They do interconnect somewhere, and the point of differentiating would likely be a service disconnecting means.